Aluminum A356/SiC/20p-T61 vs A356/SiC/20p-T7
Aluminum · A356/SiC/20p temper comparison
A356/SiC/20p-T61 and A356/SiC/20p-T7 are two conditions of the same aluminum grade, A356/SiC/20p: T61 (T6 variant, underaged) versus T7 (solution heat treated and overaged (stabilized)). The chemistry is identical, so every difference below comes from the condition. A356/SiC/20p-T61 is the stronger of the two: yield strength 325 MPa (47.1 ksi) against 255 MPa (37 ksi) for A356/SiC/20p-T7, about 27% more; tensile strength follows at 355 MPa (51.5 ksi) vs 290 MPa (42.1 ksi). In exchange, A356/SiC/20p-T7 is the more ductile: elongation 0.9% versus 0.3% for A356/SiC/20p-T61, and A356/SiC/20p-T61 is harder (125 HB vs 100 HB). A356/SiC/20p-T7 runs hotter in service (250°C vs 200°C continuous) and A356/SiC/20p-T7 conducts electricity better (30 % IACS vs 27 % IACS).
A356/SiC/20p-T61Choose it when strength drives the design.
A356/SiC/20p-T7Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.
A356/SiC/20p-T61 vs A356/SiC/20p-T7: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all aluminum grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
How to read these bars
- One bar per material. A full bar is the highest value among all aluminum grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
A356/SiC/20p-T61A356/SiC/20p-T7
Mechanical
Strength, stiffness, ductility and hardness at room temperature.
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Compressive Strength
Shear Strength
Fatigue Strength (Endurance Limit)
Fracture Toughness (K_IC)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Vickers
Same in both: Elastic (Young's) Modulus 98 GPa14.2 Msi · Shear Modulus 38 GPa5.5 Msi · Bulk Modulus 81 GPa11.7 Msi · Poisson's Ratio 0.3
Physical
Density and transition temperatures.
Same in both: Density 2.76 g/cm³0.1 lb/in³ · Melting Point (Solidus) 557°C1,035 °F · Liquidus Temperature 613°C1,135 °F
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Max Service Temperature (continuous)
Same in both: Specific Heat Capacity 854 J/kg·K0.2 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 17.5 µm/m·K9.7 µin/in·°F · Latent Heat of Fusion 300 J/g129 BTU/lb · Min Service Temperature -196°C-321 °F
Electrical
Conductivity and insulation.
Electrical Conductivity
Electrical Resistivity
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Corrosion Resistance
Same in both: Galvanic Potential (seawater, vs SCE) -0.82 V
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Machinability Rating (AISI 1212 = 100 %)
Formability (cold)
Same in both: Weldability 25 / 100 · Castability 70 / 100 · Brazeability / Solderability 30 / 100 · Polishability 45 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 235 MJ/kg101,032 BTU/lb · Embodied Carbon (primary production) 14.5 kg CO₂/kg · Embodied Water 1,150 L/kg138 gal/lb · Typical Recycled Content 10%
Strength versus weight
Yield strength against density for every aluminum grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.
A356/SiC/20p-T61 vs A356/SiC/20p-T7 — frequently asked
Is A356/SiC/20p-T61 stronger than A356/SiC/20p-T7?
Yes. A356/SiC/20p-T61 has a typical yield strength of 325 MPa (47.1 ksi) against 255 MPa (37 ksi) for A356/SiC/20p-T7 — about 27% more. Tensile strength is 355 MPa (51.5 ksi) vs 290 MPa (42.1 ksi).
Which condition does FabDigit quote by default, T61 or T7?
T6 is the default A356/SiC/20p condition in the FabDigit quote flow (neither T61 nor T7). The other condition is available on request or by drawing note — specify it in the material field or the part notes and the quote is priced for it.
When should I choose A356/SiC/20p-T61 over A356/SiC/20p-T7?
Pick A356/SiC/20p-T61 when strength drives the design. Pick A356/SiC/20p-T7 when the part is bent, formed or impact-loaded, or when the part sees heat.
Ready to make it?
Upload a CAD file and FabDigit prices the part in A356/SiC/20p-T61 and A356/SiC/20p-T7 side by side — material, machining time, tolerance and finish in one quote. Certified material data ships with the order on request.
Typical handbook values for the conditions named above, normalised for comparison. Hardness on non-Brinell scales is converted approximately for charting only. Request certified data with your order for design-critical properties.